Network Access Control (NAC) goes beyond authentication. It asks: even if you prove your identity, should your device be allowed on the network? A legitimate user with a malware-infected laptop poses a threat. NAC checks device health before granting full access.
NAC systems evaluate endpoints against security policies. They check for current antivirus, patched operating systems, disk encryption, and other compliance requirements. Non-compliant devices go to a remediation network where they can update before rejoining.